Answer:
The standard error of the mean = 2
Step-by-step explanation:
Given that:
The standard deviation σ = 14
The sample size n = 49
The sample mean
= 56
The formula for calculating the standard error can be expressed as:



S.E = 2
Therefore, the standard error of the mean = 2
Answer: 16cm
Step-by-step explanation:
l = 4w
2l + 2w = p
2(4w) + 2w = 40
8w + 2w = 40
10w = 40
w = 4 cm
l = 4w = 4(4) = 16cm
It’s C! they distributed 12 to x and 4 to get 12x+48
Answer:
25y
Step-by-step explanation:
y×25=25y
By some properties of logarithms, rewrite the equation as

so that
(<em>a</em> - 2<em>b</em>)² = <em>ab</em>
Expand the left side:
<em>a</em> ² - 4<em>ab</em> + 4<em>b</em> ² = <em>ab</em>
Rearrange terms to get a quadratic equation in <em>a</em>/<em>b</em> :
<em>a</em> ² - 5<em>ab</em> + 4<em>b</em> ² = 0
<em>b</em> must be greater than 0, otherwise log(<em>b</em>) doesn't exist, and the same goes for <em>a</em>. So we can divide by <em>b</em> ² to get
<em>a</em> ²/<em>b</em> ² - 5<em>a</em>/<em>b</em> + 4 = 0
Factorize and solve for <em>a</em>/<em>b</em> :
(<em>a</em>/<em>b</em> - 4) (<em>a</em>/<em>b</em> - 1) = 0
==> <em>a</em>/<em>b</em> = 4 or <em>a</em>/<em>b</em> = 1
However, if <em>a</em>/<em>b</em> = 1, then <em>a</em> = <em>b</em> makes <em>a</em> - 2<em>b</em> = -<em>b</em>. But we must have <em>b</em> > 0, so we omit the second solution and end up with
<em>a</em>/<em>b</em> = 4